CN109906633A - The method and apparatus for the method for EPS are moved in wireless communication system from NGS - Google Patents

Abstract

It is a kind of that user equipment (UE) is moved to the method for evolved packet system (EPS) the following steps are included: determining the step of being moved to the EPS by the UE from Successor-generation systems (NGS) in a wireless communication system；And to the EPS send radio resource control (RRC) connection request and the step of attachment request.For from the method that the NGS is moved to the EPS, if the UE has ongoing audio call when determination will be moved to the EPS, the UE maintains the ongoing audio call by executing at least one of following the two: using " carrying out audio call " call type to execute access class and forbids (ACB)；Or, sending information relevant to the ongoing audio call.

Description

The method and apparatus for the method for EPS are moved in wireless communication system from NGS

Technical field

This disclosure relates to wireless communication system, and more particularly, to the use that will have ongoing audio call The method and apparatus that family equipment (UE) is moved to evolved packet system (EPS) from Successor-generation systems (NGS).

Background technique

Wireless communication system is widely deployed to provide various types of communication services as such as voice or data. In general, wireless communication system is supported by sharing free system resources (bandwidth, transmission power etc.) between a plurality of users The multi-address system of the communication of multiple users.For example, multi-address system includes CDMA (CDMA) system, frequency division multiple access (FDMA) system System, time division multiple acess (TDMA) system, orthogonal frequency division multiple access (OFDMA) system, single-carrier frequency division multiple access (SC-FDMA) system and more Carrier wave frequency division multiple access (MC-FDMA) system.

Summary of the invention

Technical problem

One purpose of the disclosure, which is to provide, a kind of maintains that UE's is ongoing when moving between NGS and EPS as UE The method of audio call.

It will be appreciated by those of skill in the art that the purpose that can use disclosure realization is not limited to especially retouch above The purpose stated, and the above-mentioned purpose and other mesh that will be more clearly understood that the disclosure may be implemented from following detailed description 's.

Technical solution

In the one side of the disclosure, a kind of user equipment (UE) is provided in a wireless communication system from Successor-generation systems (NGS) it is moved to the method for evolved packet system (EPS).This method may comprise steps of: the UE determination will be moved to The EPS；And radio resource control (RRC) connection request and attachment request are sent to the EPS, when UE determination will move When to EPS, if UE has an ongoing audio call, UE can be by executing at least one of both following maintain Ongoing audio call: it uses " carrying out audio call " call type to execute access class and forbids ACB；Alternatively, Send information relevant to ongoing audio call.

In another aspect of the present disclosure, provides one kind and be moved in a wireless communication system from Successor-generation systems (NGS) User equipment (UE) device of evolved packet system (EPS).The UE device may include: transceiver；And processor.Processor It can be configured as determining UE and be moved to EPS, and asked to EPS transmission radio resource control (RRC) connection request and attachment It asks.When UE determination will be moved to EPS, if UE has ongoing audio call, UE can be both following by executing At least one of maintain ongoing audio call: use the execution of " carrying out audio call " call type to connect Enter class and forbids ACB；Alternatively, sending information relevant to ongoing audio call by transceiver.

Executing ACB may include: to generate random number by UE, and by random number and correspond to " carrying out audio call " Call type forbids the factor to be compared；And if random number, which is greater than, forbids the factor, it is determined that execute and connect at random Enter.

Forbid the factor that can obtain from system information.

Corresponding to " carrying out audio call " call type forbid the factor can be configured as be less than correspond to " initiating signaling " type of call forbids the factor.

When sending information relevant to ongoing audio call, the UE can by from by receive with it is ongoing It is excluded in the congestion control application that the network node of the relevant information of audio call executes.

Information relevant to ongoing audio call can correspond to " carrying out audio call " and establish reason.

" carrying out audio call " is established reason and can be included in RRC connection request, and network node can be with It is evolution node B (eNB).

Information relevant to ongoing audio call can correspond to instruction, and there are ongoing audio calls Information.

There are the information of ongoing audio call to be included in attachment request for instruction, and network node can To be mobility management entity (MME).

There are the information of ongoing audio call can be included in packet data network (PDN) connection request for instruction In, and network node can be mobility management entity (MME).

PDN connection request can be included in attachment request.

Can not have between the access and mobile management function to ps domain (AMF) of the mobility management entity (MME) and NGS of EPS Interface.

When UE is when except the coverage area of NGS, mobile determination can be carried out.

It can be to carry out mobile determination either by the selection of UE or by the instruction from NGS.

Beneficial effect

According to the disclosure, UE can while maintaining ongoing audio call therebetween not the NGS of interface and It is moved between EPS.

Those skilled in the art it should be appreciated that the effect that the disclosure is able to achieve be not limited to above specifically described it is interior Hold, and will be according to the further advantage described in detail below to be more clearly understood that the disclosure carried out in conjunction with attached drawing.

Detailed description of the invention

Attached drawing is included to provide further understanding of the disclosure, and is incorporated into a part of the application simultaneously The part of the application is constituted, attached drawing instantiates embodiment of the present disclosure and is used to illustrate the original of the disclosure together with specification Reason.In the accompanying drawings:

Fig. 1 is to illustrate the schematic diagram of the structure of the evolved packet system (EPS) including evolution block core (EPC).

Fig. 2 is to illustrate the diagram of the general frame of E-UTRAN and EPC.

Fig. 3 is to illustrate the diagram of the structure of the radio interface protocol in control plane.

Fig. 4 is the diagram of the structure of the radio interface protocol in example user plane.

Fig. 5 is to illustrate the flow chart of random access procedure.

Fig. 6 is to illustrate the diagram of the connection processing in radio resource control (RRC) layer.

Fig. 7 is to illustrate the diagram of 5G system.Fig. 8 to Figure 10 is to illustrate interworking architecture (interworking structure) Diagram.

Figure 11 is the diagram that moves between the system illustrated in interworking architecture.

Figure 12 is to illustrate the diagram of the structure of NGS and EPC.

Figure 13 and Figure 14 is the diagram for illustrating embodiment of the present disclosure.

Figure 15 is to illustrate the diagram of the configuration of the node apparatus according to embodiment of the present disclosure.

Specific embodiment

Following embodiment is the combination of component and the feature of the invention of predetermined form.Each component or feature can be with It is considered selective, unless in addition specifically mentioning.Each component or feature can by not with other components and feature group The form of conjunction executes.In addition, some components and/or characteristic can be combined, to configure embodiments of the present invention.It can change Become the sequence of operation described in embodiments of the present invention.The some components or feature of one embodiment can be included In another embodiment, or can be replaced by correspondence component of the invention or feature.

Following concrete term used in the description is provided and is to help the understanding present invention, and of the invention In the range of technical concept, the use of these concrete terms becomes another form.

In some cases, in order to avoid keeping idea of the invention fuzzy, it is convenient to omit known structure and equipment, Huo Zheke To use the block diagram in the core function for focusing on each structure or equipment.In addition, this specification in the whole text, identical attached drawing Label is used for identical component.

Embodiments of the present invention it is available for IEEE (electric electronic engineering association) 802 groups of systems, 3GPP system, The support of normative document disclosed at least one of 3GPP LTE&LTE-A system and 3GPP2 system.That is, implementation of the invention In mode in order to illustrate technical concept of the invention and the simultaneously support of the available document above of steps not described or part. Furthermore, it is possible to describe all terms disclosed in this document according to the above normative document.

Following technology can be used for various wireless communication systems.Although 3GPP LTE and 3GPP LTE-A system will be based on The system description disclosure, but it is clear that the present disclosure is not limited thereto.

Term used herein is defined as follows.

- UMTS (Universal Mobile Telecommunications System): the third generation based on GSM (global system for mobile communications) developed by 3GPP Mobile communication technology.

- EPS (evolved packet system): including the EPC as the packet-switched core network based on IP (Internet protocol) The network system of (evolution block core) and such as LTE and the such access network of UTRAN.The system is the evolution version of UMTS Network.

The base station of-NodeB:GERAN/UTRAN.The base station is installed in outdoor, and coverage area is the scale of macrocell.

The base station of-eNodeB:LTE.The base station is installed in outdoor, and coverage area is the scale of macrocell.

- UE (user equipment): UE can be referred to as terminal, ME (mobile device), MS (movement station) etc..In addition, UE can be with It is portable as such as laptop, cellular phone, PDA (personal digital assistant), smart phone and multimedia device Device.Alternatively, UE can be non-portable device as such as PC (personal computer) and car-mounted device.It is associated with MTC The term " UE " that ground uses can refer to MTC device.

- HNB (family NodeB): the base station of UMTS network.The base station is installed in interior, and coverage area is Microcell Scale.

The base station of-HeNB (family eNodeB): EPS network.The base station is installed in interior, and coverage area is Microcell Scale.

- MME (mobility management entity): the network of the EPS network of mobile management (MM) and session management (SM) is executed Node.

- PDN-GW (packet data network-gateway)/PGW:EPS network execution UE IP address distribution, grouping screening and The network node of filtering, accounting data collection etc..

- SGW (gateway): EPS network executes mobile anchor, is grouped routing, idle mode buffering of packets and MME The network node of the triggering of UE paging.

- NAS (Non-Access Stratum): the upper layer of the control plane between UE and MME.It is the use in LTE/UMTS protocol stack The functional layer of signaling and service message between UE and core network sent and received, and support UE mobility, and Support the session management procedure for establishing and safeguarding the IP connection between UE and PDN GW.

- PDN (packet data network): support the server of special services (for example, multimedia messaging service (MMS) services Device, Wireless Application Protocol (WAP) server etc.) locating for network.

- PDN connection: be represented as IP address (address IPv4 and/or an IPv6 prefix) PDN and UE it Between logical connection.

- RAN (radio access network): including NodeB, eNodeB and for control Node B in 3GPP network and The unit of the radio network controller (RNC) of eNode B is present between UE and provides the connection with core network.

- HLR (home location register)/HSS (home subscriber servers): with the number of subscriber information in 3GPP network According to library.HSS can execute such as configuration storage, Identity Management and User Status and store such function.

- PLMN (public land mobile network): for the network for providing the purpose of mobile communication service for individual and configuring. The network can be configured for each operator.

Close to service (or ProSe service or based on close service): allow for physically close to device it Between discovery, mutual direct communication/passing through the communication of base station/pass through third-party communication.At this point, user plane data passes through directly It connects data path to swap, without being subjected to 3GPP core network (for example, EPC).

EPC (evolution block core)

Fig. 1 is the schematic diagram for showing the structure of the evolved packet system (EPS) including evolution block core (EPC).

EPC is the core element of the System Architecture Evolution (SAE) for improving the performance of 3GPP technology.SAE, which corresponds to, to be used In the research project for determining the ambulant network structure between support various types network.For example, the purpose of SAE is to provide use In the packet-based system of the optimization for the data transmission capabilities supported various wireless access technologys and provide enhancing.

Specifically, EPC is the core network of the IP mobile communication system for 3GPP LTE, and can support in real time and Non real-time packet-based service.In normal mobile communication system (that is, the second generation or 3-G (Generation Three mobile communication system)), core The function of heart network is by circuit switching (CS) subdomain for voice and packet switch (PS) subdomain for data come real Existing.However, from the 3GPP LTE system that third generation communication system evolution comes, CS subdomain and PS subdomain be unified into for One domain IP.That is, in 3GPP LTE, it can be by IP-based business station (for example, eNodeB (enode B)), EPC and application domain (for example, IMS) establish the connection of the terminal with IP ability.That is, EPC is arrived for holding Hold the basic structure of IP service.

EPC may include various assemblies.Fig. 1 shows some in these components, that is, gateway (SGW), packet data Network gateway (PDN GW), mobility management entity (MME), service GPRS (General Packet Radio Service) supporting node (SGSN) and enhanced packet data gateway (ePDG).

SGW (or S-GW) is operated as the boundary point between radio access network (RAN) and core network, and Safeguard the data path between eNodeB and PDN GW.When terminal moves on the region serviced by eNodeB, SGW serves as this Ground mobility anchor.That is, the Evolved UMTS Terrestrial radio access network that grouping can define after 3GPP version 8 By being routed for ambulant SGW in network (E-UTRAN).In addition, SGW may be used as another 3GPP network (the RAN defined before 3GPP version 8, for example, (global system for mobile communications (GSM)/enhancing data transfer rate is complete by UTRAN or GERAN Ball evolution (EDGE) radio access network) ambulant anchor point.

PDN GW (or P-GW) corresponds to the endpoint of the data-interface for packet data network.PDN GW can support plan Slightly execute feature, packet filtering and charging support.In addition, PDN GW may be used as with 3GPP network and non-3 GPP network (for example, Unreliable network as such as intercommunicated wireless local area network (I-WLAN) and such as CDMA (CDMA) or WiMax network are in this way Reliable network) mobile management anchor point.

It, can basis although SGW and PDN GW is configured as individual gateway in the example of the network structure of Fig. 1 Single gateway config option realizes the two gateways.

MME executes signaling and control function to support UE to distribute the access of network connection, Internet resources, tracking, paging, Roaming and switching.MME control and subscriber and the associated control plane function of session management.MME manages numerous eNodeB and signaling, To select the conventional gateway for being switched to other 2G/3G networks.In addition, MME executes security process, terminal to network session Processing, non-occupied terminal location management etc..

SGSN processing is used for the mobile management of such as user of other 3GPP networks (for example, GPRS network) and authenticates this All packet datas of sample.

EPDG is used as the security node for non-3 GPP network (for example, I-WLAN, Wi-Fi Hotspot etc.).

As above by reference to described in Fig. 1, the terminal with IP ability can be based not only on 3GPP access but also based on non- 3GPP access, the IP service network (for example, IMS) provided by operator is accessed via the various elements in EPC.

In addition, Fig. 1 shows various reference points (for example, S1-U, S1-MME etc.).In 3 gpp, will connection E-UTRAN and The concept link definition of two kinds of functions of the different function entity of EPC is reference point.Table 1 is the column of reference point shown in Fig. 1 Table.According to network structure, other than the reference point in table 1, there may also be various reference points.

[table 1]

In reference point shown in FIG. 1, S2a and S2b correspond to non-3 gpp interface.S2a is provided to user plane The reference point of relevant control and mobility support between reliable non-3 GPP access and PDN GW.S2b is mentioned to user plane For the reference point of relevant control and mobility support between ePDG and PDN GW.

Fig. 2 is the diagram of the framework of explanatory illustration typical case E-UTRAN and EPC.

As shown in the figure, when activating radio resource control (RRC) connection, eNodeB, which can be executed, leads to gateway To UE's on routing, the scheduled transmission of paging message, the scheduling of broadcast channel (BCH) and transmission, uplink and downlink The dynamic allocation of resource, the configuration of eNodeB measurement and regulation, radio bearer control, radio admissions control and connection movement Property control.In EPC, carry out paging generation, LTE_IDLE condition managing, the encryption of user plane, SAE carrying control and The encryption of NAS signaling and integrity protection.

Fig. 3 is the diagram of the structure of the radio interface protocol in the control plane between explanatory illustration UE and base station, And Fig. 4 is the diagram of the structure of the radio interface protocol in the user plane between explanatory illustration UE and base station.

Radio interface protocol is based on 3GPP wireless access network standard.Radio interface protocol horizontally includes object Manage layer, data link layer and interconnector layer.Radio interface protocol is divided into the use for being used for transmission data information of vertical arrangement Family plane and control plane for transmitting control signaling.

Protocol layer can be classified as based on three sublayers of well known open system interconnection (OSI) model in communication system First layer (L1), the second layer (L2) and third layer (L3).

Hereinafter, it will provide and user shown in the radio protocol and Fig. 4 in control plane shown in Fig. 3 put down The description of radio protocol in face.

Physical layer as first layer uses physical channel to provide information transmission service.Physical channel level passes through transmission channel It is connect with medium access control (MAC) layer of the higher level as physical layer.Data are by transmission channel in MAC layer and PHY layer Between transmit.Executed by physical channel different physical layer (that is, physical layer of the physical layer of transmitter and receiver) it Between data transmission.

Physical channel is made of multiple subframes in time domain and multiple subcarriers in frequency domain.One subframe is by time domain Multiple symbols and multiple subcarriers composition.One subframe is made of multiple resource blocks.One resource block is by multiple symbols and multiple Subcarrier composition.The unit time of Transmission Time Interval (TTI) i.e. data transmission is 1ms, corresponds to a subframe.

According to 3GPP LTE, physical channel present in the physical layer of transmitter and receiver can be divided into and physics Downlink sharied signal channel (PDSCH) and the corresponding data channel of physical uplink shared channel (PUSCH) and and physics Downlink control channel (PDCCH), physical control format indicator channel (PCFICH), Physical Hybrid ARQ Indicator channel (PHICH) and the corresponding control channel of physical uplink control channel (PUCCH).

The second layer includes various layers.

Firstly, MAC layer in the second layer is used to various logic channel being mapped to various transmission channels, and be also used to by Various logic channel is mapped to a transmission channel.MAC layer is connect by logic channel with the rlc layer as higher.According to The type of transmitted information, logic channel are approximately separated into the control channel for the information for being used for transmission control plane and for passing The Traffic Channel of the information of defeated user plane.

Radio link control (RLC) layer in the second layer is for dividing and connecting from the received data of higher level to adjust The size of data, so that the size is suitable for lower level and sends data in radio interval.

Packet Data Convergence Protocol (PDCP) layer in the second layer executes header compression function, and header compression function reduces tool There is relatively large size and include the size of the IP packet header of unnecessary control information, so as to the wireless of narrow bandwidth High efficiency of transmission such as IPv4 or IPv6 are grouped such IP grouping in electricity interval.In addition, PDCP layers also execute safety in LTE Function, the security function is by for preventing third party from monitoring the encryption of data and for preventing third party from carrying out the complete of data manipulation Whole property protection composition.

Radio resource control (RRC) layer positioned at third layer topmost only defines in the control plane, and for matching It sets radio bearer (RB) and controls and reconfigure and discharge the related logic channel of operation, transmission channel and physical channel. RB indicates that is provided by the second layer is used to ensure the service of the data transmission between UE and E-UTRAN.

If establishing RRC connection between the rrc layer of UE and the rrc layer of wireless network, UE is in RRC connection mould Formula.Otherwise, UE is in RRC idle mode.

Hereinafter, the RRC state to UE and the description of RRC connection method will be provided.RRC state refer to the RRC of UE with State whether the RRC logical connection of E-UTRAN.With the RRC of E-UTRAN there is the RRC state of the UE of logical connection to be referred to as RRC_CONNECTED state.It is referred to as RRC_IDLE state with RRC state that the RRC of E-UTRAN does not have the UE of logical connection. UE in RRC_CONNECTED state has RRC connection, therefore E-UTRAN can identify the presence of the UE in cell unit. Correspondingly, UE can efficiently be controlled.On the other hand, E-UTRAN cannot identify the presence of the UE in RRC_IDLE state.It is in The UE of RRC_IDLE state is managed in the tracing area (TA) as the territory element bigger than the cell by core network.? That is only identifying the presence or absence of UE in the territory element bigger than cell for the UE for being in RRC_IDLE state.In order to Normal mobile communication service as such as voice service and data service is provided to the UE in RRC_IDLE state, UE should It is changed into RRC_CONNECTED state.TA is distinguished by its tracing area mark (TAI) with another TA.UE can pass through TAI is configured as the Tracking Area Code (TAC) of the information from Cell Broadcast CB.

When user first switches on UE, UE searches for cell appropriate first.Then, UE establishes RRC connection in the cell, and And by about its information registering into core network.Hereafter, UE keeps being in RRC_IDLE state.If necessary, it is in The UE (again) of RRC_IDLE state selects cell and checks system information or paging information.This operation is referred to as in cell It is resident.Only when keeping needing to establish RRC connection in the UE of RRC_IDLE state, UE just pass through RRC connection procedure and The rrc layer of E-UTRAN establishes RRC connection and is changed into RRC_CONNECTED state.UE in RRC_IDLE state is very Need to establish RRC connection in more situations.For example, these situations may include that user attempts to carry out call, attempts to send number According to or sending response message after receiving paging message from E-UTRAN.

Non-access (NAS) layer above rrc layer is set and executes function as such as session management and mobile management.

Hereinafter, it will be described in NAS shown in Fig. 3 layers.

Belong to NAS layers of eSM (evolved session management) and executes such as default bearing management and dedicated bearer management in this way Function, with control UE use come automatic network PS service.When UE is initially accessed PDN, pass through specific cluster data network (PDN) default bearing resource is assigned for UE.In this case, network distributes IP available to UE, to allow UE to take using data Business.Network is also the QoS of UE distribution default bearing.LTE supports two kinds of carryings.A kind of carry is that have for guaranteeing that data are sent With the carrying of the QoS characteristic of the ensures bit rate (GBR) of received specific bandwidth, another kind carrying be have do one's best without Guarantee the non-GBR carrying of the QoS characteristic of bandwidth.Default bearing is assigned to non-GBR carrying.Dedicated bearer, which can be assigned, to be had The carrying of the QoS characteristic of GBR or non-GBR.

Evolution packet service (EPS) carrying is referred to as by the carrying that network distributes to UE.When EPS carrying is assigned to UE When, one ID of network-assigned.This ID is referred to as EPS carrying ID.One EPS carrying has Maximum Bit Rate (MBR) and/or protects Demonstrate,prove the QoS characteristic of bit rate (GBR).

Fig. 5 is to illustrate the flow chart of the random access procedure in 3GPP LTE.

Random access procedure is by UE for obtaining synchronous with the UL of eNB or being assigned UL radio resource.

UE receives root index and Physical Random Access Channel (PRACH) configuration index from eNodeB.Each cell have by The candidate random access lead code of 64 of Zadoff-Chu (ZC) sequence definition.Root index is UE random for generating 64 candidates The logic of access lead code indexes.

The transmission of random access lead code is limited to specific time and frequency resource for each cell.PRACH configures rope Draw specific sub-frame and lead code form that instruction is wherein able to carry out the transmission of random access lead code.

UE sends randomly selected random access lead code to eNodeB.UE is in 64 candidate random access lead codes Select random access lead code, and UE selection subframe corresponding with PRACH configuration index.UE is sent in selected subframe Selected random access lead code.

When receiving random access lead code, eNodeB sends random access response (RAR) to UE.It detects in two steps RAR.Firstly, the UE detection PDCCH of random access (RA)-RNTI mask.UE is as indicated by the PDCCH detected RAR is received in MAC (medium access control) PDU (protocol Data Unit) on PDSCH.

Fig. 6 illustrates the connection procedure in radio resource control (RRC) layer.

As shown in Figure 6, according to whether establishing RRC connection RRC state is arranged.RRC state indicates the rrc layer of UE Whether entity with the entity of the rrc layer of eNodeB has logical connection.The entity of the rrc layer of the entity and eNodeB of the rrc layer of UE There is the RRC state of logical connection to be referred to as RRC connection status.The entity of the rrc layer of the entity and eNodeB of the rrc layer of UE does not have The RRC state of logical connection is referred to as RRC idle state.

UE in connection status has RRC connection, therefore E-UTRAN can identify the presence of the UE in cell unit. Correspondingly, UE can efficiently be controlled.On the other hand, E-UTRAN cannot identify the presence for the UE being in idle condition.In the free time The UE of state is managed in the tracing area as the territory element bigger than the cell by core network.Tracing area is cell The unit of set.That is, only identifying the presence or absence of UE in large area unit for the UE being in idle condition. In order to provide normal mobile communication service as such as voice service and data service to the UE being in idle condition, UE should It is changed into connection status.

When user first switches on UE, UE searches for cell appropriate first, then keeps being in idle condition.Only work as guarantor When holding the UE being in idle condition and needing to establish RRC connection, UE just passes through RRC connection procedure and the rrc layer of eNodeB establishes RRC Connection, then goes to the transformation of RRC connection status.

The UE being in idle condition is kept to need to establish RRC connection in many cases.For example, these situations may include User attempts to carry out call, attempts to send data or send response after receiving paging message from E-UTRAN to disappear Breath.

It is connect to make the UE being in idle condition establish RRC with eNodeB, needs to execute RRC as described above and connected Journey.RRC connection procedure is approximately separated into the RRC connection request message of slave UE to the eNodeB referring to Fig. 6 detailed description Transmission, the transmission of message is established in the RRC connection from eNodeB to UE and RRC connection from UE to eNodeB establishes and completes to disappear The transmission of breath.

1) when the UE being in idle condition for such as attempt called, data transmission attempt or to eNodeB paging When responding such reason and it is expected to establish RRC connection, UE sends RRC connection request message to eNodeB first.

2) when receiving the RRC connection request message from UE, ENB receives the RRC of UE in radio resource abundance Then connection request establishes message to the RRC connection that UE sends message in response.

3) when receiving RRC connection and establishing message, UE sends RRC connection setup complete message to eNodeB.Only when When UE is successfully transmitted RRC connection and establishes message, UE just establishes RRC with eNode B and connect and be changed into RRC connection mode.

MME in traditional EPC is classified as core access and movement in Successor-generation systems (that is, 5G core network (CN)) Property management function (AMF) and conversation management functional (SMF).Therefore, AMF is responsible for interacting with the NAS of UE and mobile management (MM), and SMF is responsible for session management (SM).In addition, SMF management user-plane function (UPF), UPF corresponds to for routing The gateway of customer service, that is to say, that manage the gateway of user plane.This can be construed as to imply that SMF is responsible for traditional EPC S-GW and P-GW control plane, and UPF is responsible for its user plane.In order to carry out customer service routing, in RAN and data May exist at least one UPF between network (DN).In other words, traditional EPC can be realized in 5G, as illustrated in Fig. 7. In addition, defining protocol Data Unit (PDU) session in 5G system as concept corresponding with the PDN connection in traditional EPS. PDU session means the association between UE and DN, not only provides IP type, but also provide ethernet type or unstructured type PDU connection service.In addition, uniform data management (UDM) is used as the HSS of EPC, and policy control functions (PCF) are used as EPC PCRF.In order to meet the requirement of 5G system, these functions can be extended.5G system architecture, individual function and individual interface Details can see TS23.501.

In order to which 3GPP evolved packet system (EPS) and Successor-generation systems (NGS or NG system) is (that is, next generation 5G is mobile logical Letter system) between intercommunication, need support intercommunication and migration.Hereinafter, it will be briefly described referring to Fig. 8 to Figure 11 and be used to support The solution of intercommunication and migration.

If possible, mounted E-UTRAN is upgraded, to support the new CN-RAN for NG core (NG2/NG3) to connect Mouthful.Close intercommunication between the E-UTRAN access that this method allows to upgrade and NG RAN access.

In the region that mounted E-UTRAN is not upgraded based on " double attachments " or " switching attachment " operation (that is, compared with " single radio " of low layer or " double radio " support) loose intercommunication.That is, supporting to access phase with GERAN and UTRAN The intercommunication of same type.

Fig. 8 is instantiated so that the evolution NG RAN being anchored on E-UTRA is (in the deployment scenario in annex J:TR 23.799 7) and the NG RAN (option 2 specified in the deployment scenario in annex J:TR 23.799 that is anchored on NR defined option 5 and And 4) between be capable of the system architecture of close intercommunication.

It is assumed that the mounted base station E-UTRAN is upgraded to support newly other than supporting to lead to the S1 interface of EPC CN-RAN interface (" NG2/NG3 " in Fig. 8).Further, it is assumed that NR (the annex in radio side, in addition to supporting E-UTRA anchoring Option 5 specified in deployment scenario in J:TR 23.799 and 7) except, the base station E-UTRAN after upgrading is also supported traditional LTE-Uu interface.When in tradition and the coverage area of the base station E-UTRAN of the NG UE after upgrading, they are guided to EPC, But NG UE is guided to NG core.The NAS agreement (" NG NAS ") used between NG UE and NG core is different from passing The traditional NAS agreement (" EPS NAS ") used between system UE and EPC.The accessible common subscriber database of EPC and NG core (" HSS "), but therebetween without other intercommunication interfaces.Therefore, traditional luggage of NG core is not shifted.

Fig. 9 is instantiated so that can be between GERAN, UTRA of side or non-evolution E-UTRA and the NG RAN of the other side The single system framework of the loose intercommunication of row.

In this case, the NG UE in the coverage area that GERAN, UTRAN or non-evolution E-UTRAN are accessed is drawn It is oriented to EPC.

In dual coverage (that is, not only in the range of GERAN/UTRAN/EUTRAN is accessed but also in the range of NG RAN access Interior (attachment J: option 2,4,5 and 7 specified in the deployment scenario in TR 23.799)) in the case where, UE is with " double attachments " mould Formula operation.That is, UE uses two independent systems, that is, two independent mobile management and session management context. In lower level, according to the support that will be defined by RAN working group, UE can be grasped under " single radio " or " double radio " mode Make.

The accessible common subscriber database of EPC and NG core (" HSS ").However, EPC the and NG core property of can choose is total Public PGW/SMF/IP anchor is enjoyed, (is cut similar to 3GPP-WLAN occurs in EPS to use IP address reservation function to execute switching The mode changed).Common PGW/SMF/IP anchor supports the NG11 of the MMF led in NextGen core and support is led to The NG9 of UPF in NextGen core.Support that then EPC and NG core shares public PCRF/PCF node if necessary to dynamic PCC.

Handoff procedure from source to goal systems is " switching attachment " process for being based upon 3GPP-WLAN intercommunication and defining. In goal systems, all QoS structures (that is, EPS carrying or QoS flow) is re-established completely from the beginning, and fixed later Mapping between adopted the two.

If EPC and NG core does not share public PGW/SMF/IP anchor, it can be serviced and be connected by utilization " higher " Continuous property mechanism provides service continuity in the handover.

It, can be by using double described in TS 23.237 in the case where the IMS voice service established via NG core Radio VCC (DRVCC) provide service continuity in the switching from GERAN or UTRAN.

Above-mentioned loose interworking solution also can be applied to (provide in the deployment scenario in attachment J:TR 23.799 ) be connected to the NG RAN of NG core and be connected to EPC option 3RAN between intercommunication, as illustrated in Figure 10.It is this mutual Leading to can the radio bands used in the region serviced as option 3RAN and the nothing as used in the region of NG system service The combination of line electric frequency band allows for smoothly realizing in the case where " double attachments " (or " switching attachment ") operation.Optionally The close intercommunication based on the principle derived from Fig. 8 can be used also to support the option 3RAN and NG RAN that are connected to EPC in ground Between intercommunication.It needs to upgrade for second with the E-UTRAN node of support option 3 this means that once upgrading, to support to lead to The NG2/NG3 of NG core.

Figure 11 illustrates the call flow of " switching attachment " process when UE is moved to EPS from NG system.In opposite direction Call flow is also similar.Referring to Fig.1 1, in step S1100, UE is connected to NG system and establishes PDU session.

At certain moment (for example, when UE is in the borderline region on NG system island), NG RAN instruction UE goes to target " the switching attachment " of system (that is, EPS).When UE is in NR coverage area, RAN will design the measurement of E-UTRAN cell, instead ?.

In step S1102, UE initiates the attach process for being directed to EPS.

In step S1103, as a part of attach process, UE is authenticated, and from common subscriber database (" HSS ") The middle address retrieval PGW.

In step S1104, the S5 session between the part PGW of public PGW/SMF/IP anchor and SGW, and this are established When, DL business is diverted EPS access.

In step S1105, attach process is completed by the UE that EPS is communicated.It is carried if necessary to dedicated EPS, then Information provided by based on PCR F/PCF is established as the part of attach process.

In step S1106, control plane (CP) function in NG system stores UE context during specific time period.

According to the above-mentioned solution in TR 23.799, although EPS and NGS share gateway only to simplify intercommunication therebetween Framework, but there is no interface (that is, AMF or MMF are described for managing the MME and NGS in EPS between the MM entity of system In MM control plane function).As a result, network cannot be by MM or more when UE is moved to another system from a system Text hands over to goal systems.Therefore, UE should execute attach process when changing system.For example, if UE is exhaled in execution voice New radio (NR) coverage area is removed when crying (here, audio call means PS audio call or IMS audio call) (that is, 5G Radio coverage), then RAT should be become LTE to receive service by UE.In this case, UE should be attached to EPS. However, as shown in Figure 11, when UE is moved between EPS and NGS, even if UE does not change P-GW, UE is also due to attachment behaviour The service disruption made and grown.If eNB or MME refuses and/or keeps out of the way due to the congestion in RAN and/or core network From the connection request for the UE transmission for intending to be attached to EPS network, then the audio call with real time business characteristic may be brought Negative effect, so that user experience be made to be deteriorated.

There ought be the UE of ongoing audio call to be attached due to moving between EPS and NGS therefore, it is necessary to a kind of The method for reducing out of service time when to goal systems or maintaining ongoing audio call (herein, is carrying out Audio call may include ongoing PS audio call, ongoing PS video call, ongoing IMS voice It is calling, ongoing IMS video call, ongoing MMTel calling, ongoing MMTel video, ongoing Audio call, ongoing video call etc.).

Embodiment

When UE determine be moved to EPS from NGS when, UE can to EPS send radio resource control (RRC) connection request and Attachment request.

If UE is determining there is ongoing audio call when being moved to EPS, UE can be both following by executing At least one of maintain ongoing audio call: use the execution of " carrying out audio call " call type to connect Enter class and forbids (ACB)；Or send information relevant to ongoing audio call.In other words, in order to maintain into Capable audio call, UE can with otherwise use " carrying out audio call " call type execute ACB or send with just In the relevant information of the audio call of progress.Alternatively, UE can execute the two operations.In the following, by the two are described respectively Operation.

UE predominant methods

When UE determination will be moved to EPS, if UE has ongoing audio call, UE use " is carrying out language Sound calling " call type executes ACB.Here, the execution of ACB may mean that UE create random number, by random number with Forbid the factor to be compared corresponding to " carrying out audio call " call type, then forbids if random number is greater than The factor, it is determined that execute random access.When UE, which is determined, executes random access, RRC connection request is sent eNB by UE.

Forbidding the factor is to obtain and correspond in 0 and 1 range from system information (for example, system information block (SIB)) Probability value, the probability value determination whether prevents RACH when the network is congested.Disable time again attempts to be prevented by ACB Average latency needed for before RACH.

Particularly, according to the present embodiment, correspond to " carrying out audio call " call type and forbid the factor It can be configured as to be less than and forbid the factor corresponding to " initiating signaling " type of call.It is not prevented as a result, UE can be configured as Random access procedure for ongoing audio call.

Network node predominant methods

It, can be from by receiving and ongoing voice when UE sends information relevant to ongoing audio call It calls in the congestion control application of the network node execution of relevant information and excludes the UE.Alternatively, receive with it is ongoing The network node of the relevant information of audio call can forcibly/with high probability/high priority receiving/approval from send with just The UE of the relevant information of the audio call of progress request (for example, later by the RRC connection request of description, attachment request, PDN connection (connectivity) request etc.).

As a specific example, information relevant to ongoing audio call can be " carrying out audio call " and build Vertical reason." carrying out audio call " is established reason and can be included in RRC connection request, and network node can be eNB.That is, the NAS layer of UE to AS layers of transmission with newly define to establish cause value corresponding " carrying out audio call ", To send attachment request message to network.In other words, it will thus provide be arranged to " carrying out to AS layers of cause value of establishing Audio call "." the carrying out audio call " newly defined establish cause value can indicate UE handling audio call (or There is the session for audio call).Alternatively, it may be an indicator that UE just (or has for video call in processing video frequency calling Session).It individually establishes cause value (for example, " carrying out video call ") furthermore it is possible to define and is used to indicate UE Just in processing video frequency calling.

When the AS of UE layer receive attachment request message from NAS layers and newly define when establishing cause value, AS layers pass through by Receive establish cause value include transmitted and received in RRC connection request message to eNB establish cause value.It is receiving When RRC connection request message, eNB identifies that UE sends RRC connection request when UE has the calling of ongoing voice/video, Then by considering the fact that UE sends RRC connection request when there is the calling of ongoing voice/video, determination receives RRC Connection request.This, which can be construed as to imply that, receive RRC connection request with high priority.Alternatively, this can be meaned When application congestion control when, by be prioritized RRC connection request be not applied to congestion control.Priority criteria can be meaned , with urgent, mt-Access, mo-Signalling, mo-Data, delayTolerantAccess-v1020 and mo- The cause value of establishing of at least one of VoiceCall-v1280 is compared, it has high priority.

For another example, information relevant to ongoing audio call, which can be, indicates that there are ongoing audio calls Information, and it can be sent to MME by attachment request.Specifically, when UE (that is, the NAS layer of UE or EMM layers) is to MME When sending attachment request message, UE can include the parameter newly defined in attachment request message, exist with instruction and carrying out Audio call or ongoing video call.In order to include this parameter, existing information element can be used, or can be with Define and use new information element.Single parameter can indicate that there are ongoing audio call or ongoing videos Calling, or the parameter for indicating respectively ongoing audio call and ongoing video call can be defined.

When receiving the attachment request message including the parameter newly defined, MME can identify that UE has for voice/view The session of frequency calling, being then based on UE has the fact that the session for voice/video calling, it is determined whether receives attachment request. This, which can be construed as to imply that, receive attachment request with high priority.Alternatively, this may mean that when using congestion When control, congestion control is not applied to by being prioritized attachment request.Congestion control can be MM congestion control and/or SM is gathered around Plug control.SM congestion control can be executed, so that (it is not wrapped based on the parameter newly defined included in attachment request message Include in wherein included PDN connection (connectivity) request), ESM layers of the EMM layer informing of MME there are ongoing voice/ Video call.The operation can be for supporting IMS service (or audio call, video because of requesting to connect with the PDN generated At least one of calling, MMTel voice and MMTel video) PDN connect and be performed.Alternatively, the operation can be because of The APN of PDN connection is the APN for IMS and is performed.Priority criteria may mean that, and attachment with low priority Request with without low priority and not any one of attachment request of new parameter or both is not compared, it has high priority.

For another example, there are the information of ongoing audio call can be included in packet data network (PDN) even for instruction It connects in request, network node can be MME, and PDN connection request can be included in attachment request.That is, new Parameter is added to PDN connection (connectivity) request message included in attachment request message.UE (that is, the NAS layer of UE or ESM layers) it include in attachment request message the parameter newly defined in included PDN connection (connectivity) request message, with finger Show that there are ongoing audio call or ongoing video calls.In order to include this parameter, existing letter can be used Element is ceased, or can be defined and using new information element.Single parameter can indicate that there are ongoing audio calls Or ongoing video call, or can define and indicate respectively that ongoing audio call and ongoing video are exhaled The parameter cried.

The ESM layer of UE can be indicated by EMM layers to include the presence of ongoing voice/video calling or indicate The voice/video of progress calls the information being present in PDN connection (connectivity) request message.Alternatively, it is replaced as ESM layers Generation, the EMM layer of UE may include newly define be used to indicate ongoing audio call or ongoing video call is deposited The parameter being in PDN connection (connectivity) request message included in attachment request message.Since the foregoing describe parameters Details, therefore be not repeated here.PDN connection can be for support IMS service (or audio call, video call, At least one of MMTel voice and MMTel video) PDN connect.Alternatively, the APN of PDN connection can be the APN of IMS.

When receiving the attachment request message including PDN connection (connectivity) request containing the parameter newly defined, MME It can identify that UE has the session for voice/video calling, be then based on the thing for the session that UE has for voice/video calling It is real, it is determined whether to receive the request of PDN connectivity.This can be construed as to imply that receive PDN connectivity with high priority Request.Alternatively, this may mean that when application congestion control, not be applied to gather around by being prioritized the request of PDN connectivity Plug control.Congestion control can be MM congestion control and/or SM congestion control.SM congestion control can be executed, so that being based on PDN Connect the parameter newly defined included in (connectivity) request, EMM layers of the ESM layer informing of MME there are ongoing voice/ Video call.Priority criteria may mean that, (connectivity) request be connect with PDN with low priority and without low preferential Any one of PDN connection (connectivity) request of grade and not new parameter or both is compared, it has high priority.

For another example, instruction can be sent to there are the information of ongoing audio call is included in independent PDN connection The MME requested without being included in attachment request.Furthermore, it is contemplated that not creating after UE executes attach process for branch The PDN for holding IMS service at least one of (or audio call, video call, MMTel voice with MMTel video) is connected, this PDN connection (connectivity) request message can be considered as the PDN connection for creating corresponding PDN connection and generate request.UE (that is, The NAS layer of UE or ESM layers) it include the parameter newly defined in PDN connection (connectivity) request message, to indicate exist The audio call of progress or ongoing video call.In order to include this parameter, existing information element can be used, or It can define and using new information element.Single parameter can indicate that there are ongoing audio calls or ongoing Video call, or the parameter for indicating respectively ongoing audio call and ongoing video call can be defined.It can With presence or the ongoing language of instruction for indicating the ESM layer of UE by EMM layers to include ongoing voice/video calling Audio/video calls the information being present in PDN connection (connectivity) request message.

When receiving PDN connection (connectivity) request message including the parameter newly defined, MME can identify that UE has For the session of voice/video calling, being then based on UE has the fact that the session for voice/video calling, it is determined whether connects It is requested by PDN connectivity.This can be construed as to imply that receive the request of PDN connectivity with high priority.Alternatively, this It may mean that when application congestion control, be not applied to congestion control by being prioritized the request of PDN connectivity.Priority mark It will definitely be it is meant that connecting (connectivity) request and without low priority and not new parameter with PDN with low priority Any one of PDN connection (connectivity) request or both is compared, it has high priority.

The example 1 of specific moving process

Figure 13 instantiates UE in detail and is then serviced and being moved to EPS from 5G system by EPS by 5G system service first Process.The example of the specific moving process illustrated in the example and Figure 14 of the specific moving process illustrated in Figure 13 is based on figure Interworking architecture between the 5G system illustrated in 12 and EPS.HSS+UDM as common subscriber information server is used for two Intercommunication between a system.In addition, SMF+PGW-C and UPF+PGW-U are used for the intercommunication between PDU session and PDN connection.So And there is no interface between MME and AMF.

3, UE executes registration process into S1303 in step S1301 referring to Fig.1, is serviced with receiving from 5G system.Operation is thin Section can see the clause 4.2.2.2.2 (general registration) of TS 23.502.During registration process, AMF is infused in HSS+UDM Volume it be the service node of UE and obtain subscriber information/UE context.In step S1304, UE is executed for creating PDU meeting The process of words.Details of operation can see the clause 4.3.2 (PDU session establishment) of TS 23.502.In the same of creation PDU session When, it is service node for corresponding PDU session that SMF+PGW-C registers it in HSS+UDM.If UE creates multiple PDU Session, then repeatedly step S1304.

In step S1305, UE executes call setup due to the generation that mobile originating or mobile terminating call.This Corresponding to the IMS session establishment operation based on IMS, and its details can see TS 23.228.In this step, it needs to hold The process gone for modifying PDU session, with QoS needed for meeting voice or video call.Its details can see TS 23.502 Clause 4.3.3 (PDU session modification) and TS 23.501 clause 5.7 (QoS model).If UE intends to create audio call, PDU session should be then modified, so that meeting the QoS characteristic with 5G QoS identification symbol (5QI) 1.

In step S1306, UE handles calling and its target after call set-up is completed.

In step S1307, UE determination is moved to EPS.It can be for various reasons (for example, when UE removes 5G system When coverage area or according to the selection of UE/ user) carry out the determination.Then, UE is attached to EPS.For this purpose, the NAS layer of UE is created Attachment request message is built, cause value and type of call value are established in configuration, then will establish cause value and type of call value and attachment Request message is transmitted to the AS layer of UE together.Due to the foregoing describe the details for establishing cause value and type of call value, this In without repeat.Attachment request message includes along with attach process for requesting the PDN connection for forming PDN connection (to connect Connecing property) request message.Attachment request message and/or PDN connection (connectivity) request message may include as described above and just In the relevant information of the audio call of progress.

The AS layer of UE is executed access class based on the information received from NAS layers and (ACB) is forbidden to operate.This can be explained To mean when there is ACB information corresponding with the type of call received from eNB, ACB operation is executed based on ACB information.

In step S1308, UE (that is, AS layer of UE) sends RRC connection request message to eNB.In this case, exist It is included in RRC connection request message in step S1307 from the cause value of establishing that the NAS layer of UE is transmitted to its AS layers.

In step S1309, eNB sends RRC connection foundation to UE in response to the RRC connection request message that sends from UE Message.ENB can be established cause value and determined and receive or refusal asking from UE based on included in RRC connection request It asks.When eNB refuses the request, eNB sends RRC connection reject message to UE.

As described above, establishing cause value based on included in RRC connection request message, eNB is identified to be had in UE UE sends RRC connection request when the voice/video calling of progress, then by considering that UE is having ongoing voice/video The fact that RRC connection request is sent when calling, determination receives RRC connection request.For example, in case of congestion, eNB can lead to Crossing to establish cause value and be configured to MO signaling makes to have the UE of ongoing voice/video calling prior to sending RRC connection The UE of request, to receive the RRC connection request from the UE called with ongoing voice/video.

In step S1310, after eNB receives RRC connection request, UE sends RRC connection foundation to eNB and completes to disappear Breath.When configuring RRC connection setup complete message, the AS layer of UE includes from its NAS layers of received attachment request message.

In step S1311, attachment request message is transmitted to MME by eNB.MME can be used and ongoing voice Relevant information (for example, there are the parameters that ongoing voice/video calls for instruction) is called to receive or refuse to determine Exhausted attachment request message.For example, when the network is congested, MME can indicate that there are ongoing voice/videos by making to send The UE of the parameter of calling is not prior to sending the UE of this parameter, to receive the attachment request from the UE for sending this parameter, The middle UE for sending this parameter is by including sending this parameter in attachment request by the parameter.

In step S1312, determine receive attachment request after, MME registered in HSS+UDM it be UE service section It puts and obtains subscriber information/UE context.It particularly, include for being created in 5G system by UE from the information that HSS+UDM is obtained The SMF+PGW-C information for the PDU session built.

In step S1313, MME, which can be used, indicates the parameter called there are ongoing voice/video to determine It is to receive or refuse PDN connection (connectivity) request included in attachment request message.For example, in case of congestion, APN corresponding to PDN connection can be by making by including relevant with ongoing audio call in PDN connection request Information (for example, instruction there are the parameters that ongoing voice/video call) requests the UE of generation PDN connection prior to not having There is the UE including this parameter, receives from described by including related to ongoing audio call in PDN connection request Information (for example, instruction there are the parameters that ongoing voice/video call) request the PDN of the UE of generation PDN connection Connection request.

After determining that receiving PDN connection generates request, MME can determine that MME needs to request to which SMF+PGW-C PDN connection, this should be generated based on the SMF+PGW-C information obtained in step S1312 from HSS+UDM.By working as The data network title (DNN) of the corresponding PDU session generated in 5G system is equal to the access for the PDN connection that will be generated in EPS Using the SMF+PGW-C information of PDU session when point title (APN), so that this may be able to carry out.That is, working as PDU When the DNN of session is the DNN for IMS, SMF+PGW-C, which registers it in HSS+UDM and serves in step S1304, to be directed to The PDU session of the DNN creation of IMS.That is, MME can be determined after obtaining information from HSS+UDM in step S1312 MME should send to which SMF+PGW-C and generate request, to generate the PDN connection of the APN for IMS.MME is via S-GW PDN is established with SMF+PGW-C to connect.

In step S1314, MME sends attachment received message to UE.The details of the attached operation of UE can see TS 23.401 clause 5.3.2.1 (E-UTRAN initial attachment).

In step S1315, UE can be continued UE and be held in 5G system by the PDN connection created in EPS Capable calling.For QoS needed for meeting voice or video call, the mistake for modifying PDN connection should be also executed in EPS Journey.The process can be initiated by UE or SMF+PGW-C.When UE initiates the process, UE can be attached in receiving step S1314 The process initiated after received message for requesting network creation dedicated bearer is connect, to meet needed for voice or video call QoS.Its details can see the clause 5.4.5 (the bearing resource modification of UE request) of TS 23.401.Alternatively, as UE's Substitution, SMF+PGW-C can initiate the generation of dedicated bearer, with QoS needed for meeting voice or video call.SMF+PGW-C The PDU session for the same services (that is, IMS service) in 5G system can be served due to it and carry out it is determined above, and And/or person it can based on MME request PDN connection generation when include information indicate that there are ongoing voice/views The parameter of frequency calling is determined.The details of the process of SMF+PGW-C creation dedicated bearer can see the clause of TS 23.401 5.4.1 (dedicated bearer activation).It needs to create 5QI=1 pairs had with 5G system for example, UE or SMF+PGW-C can be determined The dedicated bearer of the QCI=1 answered.

Notwithstanding the PDN connection generated during attach process for IMS, but can also be after attach process Generate the PDN connection for being used for IMS.In this case, as described above, when request PDN connection generation when, UE can will with The relevant information of the audio call of progress (that is, there are the parameters that ongoing voice/video calls for instruction) is included in PDN company It connects in (connectivity) request message.

The example 2 of specific moving process

Figure 14 instantiates then mistake that UE is serviced and being moved to EPS from 5G system by EPS by 5G system service first Journey.Figure 14 and Figure 13 the difference is that, UE executes tracking area update (TAU) operation rather than attached operation, so as to from EPS Receive service.Even if that is, UE has also been registered in 5G system since 5G system is different from EPS, therefore UE is executed TAU is to inform its position change, and non-executing is used for the attached operation of the initial registration in system.However, due to according to this public affairs Being opened between MME and AMF does not have interface, therefore MME can not obtain the context of UE, therefore send TAU refuse information to UE, with Inform that TAU request is rejected.As a result, UE executes the attached operation for being directed to EPS.

Hereinafter, the specific characteristic of Figure 14 will be described, and assume other unmentioned steps be equal to above by reference to The step of Figure 13 is described.

Step S1401 to S1406 is respectively equivalent to the step S1301 to S1306 of Figure 13.

In step S1407, UE is because it determines except the coverage area of 5G system and be moved to EPS.Therefore, UE tastes Test point executes TAU to EPS.Specifically, the NAS layer of UE creates TAU request message, and cause value and type of call value are established in configuration, Then AS layer cause value and type of call value will be established be transmitted to UE together with TAU request message.Since the foregoing describe build The details of vertical cause value and type of call value, therefore be not repeated here.TAU request message may include with it is ongoing The relevant information of audio call (for example, there are the parameters that ongoing voice/video calls for instruction).In TAU request message The identifier of included UE is based on the identifier provided when UE is registered in 5G system by AMF.In other words, UE Identifier can be the interim ID based on the UE provided by AMF configuration ID.

The AS layer of UE executes access class quiescing based on the information received from NAS layers.This can be interpreted to anticipate Taste when exist ACB information corresponding with the type of call received from eNB when, based on ACB information execute ACB operation.

Step S1408 to S1409 is respectively equivalent to the step S1308 to S1309 of Figure 13.

In step S1410, after eNB receives RRC connection request, UE sends RRC connection foundation to eNB and completes to disappear Breath.When configuring RRC connection setup complete message, the AS layer of UE includes from NAS layers therein received TAU request message.

In step S1411, TAU request message is transmitted to MME by eNB.Included by MME inspection TAU request message The identifier of UE.The interim ID of UE as described in step S1407 is supplied to configure ID based on AMF, is not had with AMF The MME of interface can not handle TAU request.In other words, MME can not receive the context of UE from AMF.Therefore, MME determination is refused Exhausted TAU request.

In step S1412, MME sends TAU refuse information to UE.According to the prior art, when MME determines network congestion When, MME may include temporal information, to prevent UE from requesting mobile management (MM) when sending TAU refuse information.Namely It says, MME can be configured the value of T3346 (back off timer) by its expectation, then by including refusing in TAU by T3346 value It is sent in message.In receiving TAU refuse information when included T3346 value, UE cannot be sent out during the corresponding time Send attachment request message, TAU request message, service request information etc..Here, T3346 value may be several hours.T3346's Details can see TS 24.301 and TS 24.008.However, even if in case of congestion, MME can also be requested based on TAU There are the parameters that ongoing voice/video calls not to provide T3346 value to UE to determine for included instruction in message.Cause This, UE can send attachment request after receiving TAU refuse information immediately.

In step S1413, UE refuses to be attached to EPS to determine based on the TAU received.The NAS layer of UE generates attachment Request message, configuration establish cause value and type of call value, then will establish cause value and type of call value disappears with attachment request Breath is transmitted to the AS layer of UE together.Since the foregoing describe the details for establishing cause value and type of call value, here not into Row repeats.Attachment request message includes along with attach process for requesting the PDN connection (connectivity) for forming PDN connection to be asked Seek message.Attachment request message and/or PDN connection (connectivity) request message may include above-mentioned exhaling with ongoing voice It is relevant information.

UE (that is, AS layer of UE) sends RRC connection request message to eNB.In this case, in step S1407 from The cause value of establishing that the NAS layer of UE is transmitted to its AS layers is included in RRC connection request message.RRC connection is being sent to eNB Before request message, UE can execute the operation of ACB described in step S1407 again.

Step S1414 to S1420 is respectively equivalent to step S1309 to S1315.

It is clear that despite it is assumed that the disclosure that UE is described under the premise of being moved to EPS from NGS, but when UE is pressed When being moved to NGS from EPS as former state or after being modified by those skilled in the art, the disclosure can be applied.For example, Above-mentioned mechanism can be modified and be applied to NGS UE and NGS network entity/function.Since NGS has for handling MM The heterogeneous networks of NAS message and SM NAS message entity/function, therefore can be for this modification disclosure.

In addition, the NAS layer of UE can identify in various ways and carry out voice/video calling, these modes include Explicit and implicit method.For example, IMS layers can inform NAS layers, there are the calling of ongoing voice/video or source systems NAS layer can inform the NAS layer of goal systems there are the callings of ongoing voice/video (that is, when UE is from NGS When being moved to EPS, NAS layers of NGS can notify NAS layers of EPS that there are the callings of ongoing voice/video, and when UE from When EPS is moved to NGS, NAS layers of NPS can notify NAS layers of NGS that there are the callings of ongoing voice/video).

Although laying particular emphasis on the case where UE is attached to goal systems describes the disclosure, when UE intends in goal systems When being operated in (from from the point of view of RAN and/or CN) with connection mode, that is to say, that when the message for being used for it is sent net by UE When network (e.g., when UE executes TAU, location updating, service request etc.), the disclosure can also be applied.

In addition in attachment request message it is included newly define establish cause value, type of call value, parameter value and PDN In connectivity request message except included parameter value, can also individually it be worth for ongoing IMS urgent call definition. Alternatively, (one or more) value newly defined can be used for ongoing IMS urgent call.

In addition, although UE executes TAU (that is, location update operations corresponding with the TAU of NGS is directed to) for goal systems, But when UE receives TAU refusal from network, UE can execute attach process.In this case, TAU refusal can be explicit Or implicitly include for allow UE execute attach process information.

Although the disclosure describes network node/function, process etc. with reference to EPS, the network section of 5G system can be used Network node/the function and process of point/function and process replacement EPS.For example, (initial) registration process, cancellation can be used respectively Process, access and mobile management function to ps domain (AMF), data network title (DNN) and PDU session replacement attach process separated Journey, MME, APN are connected with PDN.It is different from EPS in 5G system, it can during attach process (that is, during initial registration) Not create PDU session.That is, attach process can be executed only for attachment, and after completing the process, it can To start PDU session.In this case, this should be construed as to imply that the disclosure is applied to all PDU created by UE Session.

Figure 15 is instantiated according to the UE device of embodiment of the present disclosure and the configuration of network node device.

Referring to Fig.1 5, the UE device 100 according to the disclosure may include transceiver 110, processor 120 and memory 130. Transceiver 110 may be configured to send to external device (ED) and receive various signals, data and information from external device (ED).UE device 100 can wiredly and/or wirelessly connect with external device (ED).Processor 120 can be configured as the entirety of control UE device 100 Operation, and handle the information to exchange between UE device 100 and external device (ED).Memory 130 can be configured as pre- Storage treated information during fixing time, and it can the replacement of the component as such as buffer (not shown). In addition, processor 120 can be configured as the UE operation for executing and proposing in the disclosure.

Referring again to Figure 15, network node device 200 may include transceiver 210, processor 220 and memory 230.It receives Hair device 210 may be configured to send to external device (ED) and receive various signals, data and information from external device (ED).Network node Device 200 can wiredly and/or wirelessly be connect with external device (ED).Processor 220 can be configured as control network node dress 200 integrated operation is set, and handles the information that will be exchanged between network node device 200 and external device (ED).Memory 230 It can be configured as storage treated information during the scheduled time, and it can be by such as buffer (not shown) Such component replacement.In addition, processor 220 can be configured as the network node operation for executing and proposing in the disclosure.Tool Body, when UE, which is determined, is moved to EPS, processor 220 can be configured as to EPS and send radio resource control (RRC) even Connect request and attachment request.

When UE determination will be moved to EPS, if the UE has ongoing audio call, UE can pass through execution It is at least one of both following to maintain ongoing audio call: to use " carrying out audio call " type of call to believe Breath executes access class and forbids (ACB)；Or information relevant to ongoing audio call is sent by transceiver.

UE device 100 and network node 200 may be implemented so that the various embodiments for independently applying the disclosure, Or two or more embodiments are applied simultaneously.For the sake of clarity, redundancy description is omitted.

Embodiment of the present disclosure can pass through various devices (for example, hardware, firmware, software or combinations thereof) Lai Shixian.

In hardware configuration, embodiment of the present disclosure can be by one or more specific integrated circuits (ASIC), number Word signal processor (DSP), digital signal processing device (DSPD), programmable logic device (PLD), field programmable gate array (FPGA), processor, controller, microcontroller, microprocessor etc. are realized.

It in firmware or software configuration, can be with shapes such as module, process, functions according to the method for embodiment of the present disclosure Formula is realized.Software code can be stored in storage unit and be executed by a processor.Memory is located at processor It is internal or external, and data can be sent to processor via various any means knowns and receive data from processor.

As previously mentioned, the detailed description to the preferred embodiment of the disclosure is had been presented for, so that the technology of this field Personnel are able to achieve and execute the disclosure.Although reference has been made to the preferred embodiment of the disclosure above, the skill of this field Art personnel will be understood that, can the disclosure be carry out various modifications and be changed within the scope of this disclosure.For example, the technology of this field Personnel component combination described in embodiment of above can be carried out using.Therefore embodiment of above is understood to all Aspect be all it is illustrative, and not restrictive.The scope of the present disclosure should be by the attached claims and its legal equivalents Rather than above description limits, and all changes fallen into the meaning and equivalency range of the attached claims should all be wrapped Containing herein.

Industrial applicibility

Although describing the various embodiments of the disclosure based on 3GPP system, these embodiments can be with phase It is applied to various mobile communication system with mode.

Claims (15)

1. the side that a kind of user equipment (UE) is moved to evolved packet system EPS from Successor-generation systems NGS in a wireless communication system Method, method includes the following steps:

The EPS will be moved to by being determined by the UE；And

Radio resource control RRC connection request and attachment request are sent to the EPS,

Wherein, described if the UE has ongoing audio call when the UE determination will be moved to the EPS UE maintains the ongoing audio call by executing at least one of following the two: use " is carrying out voice Calling " call type executes access class and forbids ACB；Or send letter relevant to the ongoing audio call Breath.

2. according to the method described in claim 1, wherein, execute the ACB the following steps are included:

Random number is generated by the UE, and by the random number and corresponds to described " carrying out audio call " type of call Information forbids the factor to be compared；And

If the random number forbids the factor described in being greater than, it is determined that Yao Zhihang random access.

3. according to the method described in claim 2, wherein, described to forbid the factor obtained from system information.

4. according to the method described in claim 3, wherein, corresponding to " carrying out audio call " call type and forbidding The factor, which is configured as being less than, forbids the factor corresponding to " initiating signaling " type of call.

5. according to the method described in claim 1, wherein, when sending information relevant to ongoing audio call, institute UE is stated to be arranged from the congestion control application executed by the network node for receiving information relevant to ongoing audio call It removes.

6. according to the method described in claim 5, wherein, information relevant to ongoing audio call corresponds to " Carry out audio call " establish reason.

7. according to the method described in claim 6, wherein, " the carrying out audio call " establish reason be included in it is described In RRC connection request, and wherein, the network node is evolution node B, i.e. eNB.

8. according to the method described in claim 5, wherein, information relevant to ongoing audio call corresponds to instruction and deposits In the information of the ongoing audio call.

9. according to the method described in claim 8, wherein, there are the information of ongoing audio call to be included in institute for instruction It states in attachment request, and wherein, the network node is mobility management entity MME.

10. according to the method described in claim 8, wherein, there are the information of ongoing audio call to be included in for instruction In packet data network PDN connection request, and wherein, the network node is mobility management entity MME.

11. according to the method described in claim 10, wherein, the PDN connection request is included in the attachment request.

12. according to the method described in claim 1, wherein, the access of the mobility management entity MME and the NGS of the EPS There is no interface between mobile management function to ps domain AMF.

13. according to the method described in claim 1, wherein, being moved when except coverage area of the UE in the NGS It determines.

14. according to the method described in claim 1, wherein, by the selection of the UE or pass through the instruction from the NGS To carry out mobile determination.

15. a kind of user equipment (UE) dress for being moved to evolved packet system EPS from Successor-generation systems NGS in a wireless communication system It sets, the UE device includes:

Transceiver；And

Processor,

Wherein, the processor is configured to determining that the UE is moved to the EPS, and radio money is sent to the EPS Source controls RRC connection request and attachment request, and

Wherein, described if the UE has ongoing audio call when the UE determination will be moved to the EPS UE maintains the ongoing audio call by executing at least one of following the two: use " is carrying out voice Calling " call type executes access class and forbids ACB；Or it is sent and the ongoing voice by the transceiver Call relevant information.